Over the years, considerable attention has been given to systems for cleaning swimming pools. In most larger swimming pools, a circulation system is provided for filtering the water. The circulation system includes a surface water skimmer and a main drain which are in communication with a suction pump at the filter station. The pump draws off water from the pool for processing. The purified water is returned to the pool through a pressurized outlet. While the water is out of the pool, it can also be heated.
Particulates which are drawn in with the water through the main drain are collected at the filter. Surface debris is collected in the skimmer. While this approach removes a significant amount of dirt from a pool, additional steps must be taken to maintain a clean pool.
For example, manual cleaning systems are used to permit the pool owner to vacuum the pool. These manual systems, however, require a significant amount of time each week to maintain the cleanliness of the pool. Therefore, various automatic cleaning systems have been developed.
One type of automated system, which can be termed a water jet system, uses a buoyant power head connected to a water pressure source. One such pool cleaner, disclosed in U.S. Pat. No. 3,291,145 to Arneson Products, Inc., includes a pair of flexible hoses extending downwardly from a programed buoyant power head. The hoses have nozzles through which high pressure water streams are ejected. As the buoyant power head moves about the surface of the pool, the cleaner hoses sweep the dirt film from the bottom and the sides of the pool and the debris from the bottom of the pool towards the main drain at the pool's lower end. Waterlogged leaves and large debris collected in one place can then be removed from the pool. Floating leaves and other material are driven to the edge of the pool where they are removed by the pool skimmer. The device in the latter patent utilizes an additional high power pressure pump to deliver approximately 50 pounds per square inch of pressure. Where energy costs are significant, the need for an additional pressure pump was found undesirable.
Accordingly, there has been developed another automatic pool cleaner which operates on a lower pressure system. In fact, it is designed to operate off the outward fluid flow generated by the standard pool circulation system. The latter device uses a manifold to further pressurize the water from within the device itself. The details of the latter device are described in detail in copending application, Ser. No. 541,193, filed Oct. 12, 1983, and now U.S. Pat. No. 4,526,186, the disclosure of which is incorporated herein by reference. A device of the type disclosed in the latter patent is marketed by Arneson Products, Inc. under the TURBO SWEEP trademark.
As disclosed in the latter application, a restrictor valve is utilized to build up back pressure sufficient to power the device. Specifically, the water pressure of a typical filter pump will be at 8-12 P.S.I. The valve is used to boost the pressure to about 16-22 P.S.I. The valve is also used to direct any excess flow to the pool return. The amount of flow directed to the return would depend on the back pressure which can be generated by the combination of the pump and the restriction in the valve. In practice, when the filter is clean, pressures in the 22 P.S.I range, can easily be generated and supplied to the pool cleaner. In this case, a significant portion of the fluid flow will be directed by the valve to the pool return. As the filter becomes clogged, the pressure which can be generated is reduced, such that the flow to the pool return must be further reduced in order to maintain proper operating pressure for the pool cleaner.
The restrictor valve can be defined by a simple device which is manually adjusted to ensure that the proper pressure delivered to the pool cleaner. The latter patent application disclosed another valve which is automatically adjustable, through an internal ball check valve, to control the pressure to the pool cleaner.
One of the problems with these director valves is that they restrict fluid flow in order to increase pressure. This restriction, which can reduce flow from 40 gallons per minute down to 15 gallons per minute, results in the drastic increase in the time it takes to circulate and filter all the water in the pool. To maximize the filtering operation, the flow of fluid to the pool return should be unrestricted. To insure that debris is swept from the pool, both the pool cleaner and the filter system need to be operated. It would be desirable to provide a valve which can satisfy both these objects. It would also be desirable to provide a valve which automatically adjusted the pressure delivered to the pool cleaner.
The pool cleaning devices discussed above all operate on a water pressure supply. Recently, there have been developed other automatic pool cleaning systems that rely on suction. One such device is disclosed in U.S. Pat. No. 4,434,519 to Raubenheimer, issued Mar. 6, 1984, the disclosure of which is incorporated herein by reference. A device made in accordance with the teachings of the latter patent is marketed by Aquanaut, Inc., under the trademark POOL VAC.
The latter device consists of a housing to which a vacuum hose is connected. The other end of the vacuum hose is connected to the vacuum source at the skimmer of the pool. The suction of the water through the device causes an internal turbine to rotate. The turbine is operatively connected to a pair of rocking feet or pods, enabling the device to move around the bottom and sidewall surfaces of the pool. Dirt and other debris are drawn into the device and carried by the suction hose into the skimmer of the pool.
The latter device provides a very effective means for cleaning the surfaces of the pool. Unfortunately, because the hose is connected to the skimmer outlet, the skimmer is disabled. Therefore, the efficiency of removal of debris from the upper surface of the pool is reduced. Pool owners are required to manually connect and disconnect the suction hose to the cleaner to permit the alternate operation of either the skimmer or the automatic pool cleaner. It would be desirable to provide the pool owner with a valve that automatically switched functions between the pool skimmer and vacuum pool cleaner.
In most pool cleaning systems, a timer is utilized to intermittently actuate the filter pumps. For example, the filter system may be turned on to operate for a few hours in the early morning and late evening. Thus, a valve which was responsive to changes in fluid flow would be suitable for use in the subject system.
In the prior art, a number of automatic cycling valves have been developed. For example, U.S. Pat. Nos. 3,018,788 and 3,147,770 to Perlis, and U.S. Pat. No. 4,116,216 to Rosenberg, all disclose automatic valves which index upon an interruption or reduction of fluid flow. Unfortunately, the valves disclosed in the above cited patents are relatively complex and utilize an internal piston that is intricate and difficult to manufacture. Furthermore, these valves are not designed to operate under low negative pressure (suction) conditions. Accordingly, it would be desirable to provide an automatic valve which was simpler in construction and could be manufactured at lower cost.
Therefore, it is an object of the subject invention to provide a new and improved automatic valve.
It is another object of the subject invention to provide a new and improved valve for automatically controlling the direction of fluid flow.
It is a further object of the subject invention to provide a new and improved automatic valve which is indexable.
It is still another object of the subject invention to provide a new and improved valve which is indexable based on the intermittent flow of fluid.
It is still a further object of the subject invention to provide an automatic valve for use with automatic pool cleaning systems.
It is still another object of the subject invention to provide a new and improved valve for use with automatic pool cleaning systems based on suction.
It is still a further object of the subject invention to provide a new and improved automatic valve for use with pool cleaners that utilize fluid pressure.
It is still another object of the subject invention to provide a new and improved valve which can automatically regulate the pressure delivered to a pool cleaner.